Search for dissertations about: "three-dimensional grids"

Showing result 1 - 5 of 17 swedish dissertations containing the words three-dimensional grids.

2. 1. Hybrid Grid Generation for Viscous Flow Computations Around Complex Geometries

   Author : Lars Tysell; Laszlo Fuchs; Nigel P. Weatherill; KTH; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; grid generation; unstructured grids; hybrid grids; surface grids; three-dimensional grids; adaptive grids; moving grids; grid quality; accuracy; Fluid mechanics; Strömningsmekanik;

   Abstract : A set of algorithms building a program package for the generation of twoandthree-dimensional unstructured/hybrid grids around complex geometrieshas been developed. The unstructured part of the grid generator is based on the advancing frontalgorithm. READ MORE

4. 2. Modeling and optimization of least-cost corridors

   Author : Lindsi Seegmiller; Takeshi Shirabe; Kai-Florian Richter; KTH; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; raster data modeling; raster-based geographic information systems; route planning; optimal routing; corridor; wide path; corridor width; distortion; three-dimensional grid; rasterdatamodellering; rasterbaserade geografiska informationssystem; ruttplanering; optimal dirigering; korridor; bred väg; korridorbredd; distorsion; tredimensionellt rutnät; Geoinformatics; Geoinformatik;

   Abstract : Given a grid of cells, each having a value indicating its cost per unit area, a variant of the least-cost path problem is to find a corridor of a specified width connecting two termini such that its cost-weighted area is minimized. A computationally efficient method exists for finding such corridors, but as is the case with conventional raster-based least-cost paths, their incremental orientations are limited to a fixed number of (typically eight orthogonal and diagonal) directions, and therefore, regardless of the grid resolution, they tend to deviate from those conceivable on the Euclidean plane. READ MORE

5. 3. Three-Dimensional Modelling and Inversion of DC resistivity and Time Domain EM data using Multi-Resolution Framework

   Author : Jingyu Gao; Thorkild Maack Rasmussen; Maxim Smirnov; Bülent Tezkan; Luleå tekniska universitet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; DC Resistivity; time-domain electromagnetic; forward modelling; data inversion; Prospekteringsgeofysik; Exploration Geophysics;

   Abstract : 3-D forward modelling and inversion techniques play an important role in data interpretation, but they are still computationally challenging tasks. Therefore, this thesis aims to improve forward modelling and inversion performance using novel multi-resolution (MR) grid approach. READ MORE

6. 4. Distance Functions and Image Processing on Point-Lattices : with focus on the 3D face- and body-centered cubic grids

   Author : Robin Strand; Gunilla Borgefors; Stina Svensson; Christer Kiselman; David Coeurjolly; Uppsala universitet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; Computerized image analysis; digital geometry; distance functions; non-standard grids; point-lattices; Image analysis; Bildanalys;

   Abstract : There are many imaging techniques that generate three-dimensional volume images today. With higher precision in the image acquisition equipment, storing and processing these images require increasing amount of data processing capacity. Traditionally, three-dimensional images are represented by cubic (or cuboid) picture elements on a cubic grid. READ MORE

7. 5. An Object-Oriented Framework for PDE Solvers

   Author : Krister Åhlander; Michael Thuné; Uppsala universitet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; PDE; Navier-Stokes; object-oriented; overlapping grids; Numerical Analysis; Numerisk analys;

   Abstract : The issue of how to develop reusable software in scientific computing is addressed. With object-oriented analysis and design, an extendable set of collaborating objects - a framework named COMPOSE - is suggested in the area of "PDE solvers", i.e., programs that numerically solve partial differential equations (PDEs). READ MORE